Intraoperative detection of electrode lead misplacement during a lead insertion procedure

An exemplary diagnostic system may be configured to direct an acoustic stimulation generator to apply acoustic stimulation to a recipient of a cochlear implant during an insertion procedure in which an electrode lead coupled to the cochlear implant is supposed to be inserted into a cochlea of the recipient, direct the cochlear implant to use an electrode on the electrode lead to record an evoked response signal that occurs within the recipient in response to the acoustic stimulation, detect an anomaly in the evoked response signal, and determine, based on the anomaly, that the electrode lead is being inserted into a vestibular canal instead of into the cochlea.